Bluesky character limits and image sizes
This page lists every Bluesky text limit and upload size tracked by the tool, including the point where Bluesky truncates a post in the feed. Counts follow how Bluesky itself measures text, not raw string length.
Bluesky character limits
| Field | Limit | Visible in feed |
|---|---|---|
| Post | 300 | — |
| Bio | 256 | — |
“Visible in feed” is roughly where the platform collapses the rest behind a “more” link. It is the practical limit for anything you need read.
Bluesky image and video sizes
| Placement | Dimensions | Ratio | Type |
|---|---|---|---|
| Post image | 1,200 × 675 | 16:9 | Image |
| Header banner | 1,500 × 500 | 3:1 | Cover |
Limits for other networks
Limits are checked against public platform documentation and change occasionally — verify anything business-critical. Limits last reviewed .